This invention relates to location-based services and, in particular, to more accurately determining the physical location of Unlicensed Mobile Access (UMA) mobile devices for special number calls and location-based services. More particularly, a UMA Network Controller (UNC) connects to a location system to provide access point identifiers (AP-ID's) to the location system, where the location system uses the AP-ID's to determine the location of the mobile device for call routing and other purposes.
In the United States, basic 9-1-1 service is an emergency reporting service where a calling party can dial 9-1-1 in emergency situations. The call is answered at a Public Safety Answering Point (PSAP, also known as a “Public Safety Access Point”). An operator at the PSAP converses with the calling party to determine information on the emergency situation. For instance, the operator may ask the calling party for his/her name, the nature of the emergency, the location of the emergency, etc. Based on the information gathered by the operator, the operator then contacts emergency personnel to respond to the emergency.
Enhanced 9-1-1 service (E9-1-1) has the added feature of automatically providing the operator with some information on the calling party. For instance, E9-1-1 service includes the added features of Automatic Number Identification (ANI) and Automatic Location Identification (ALI). With Automatic Number Identification (ANI), the operator is automatically provided with the telephone number of the phone placing the call for emergency services (e.g., a 9-1-1 call). With Automatic Location Identification (ALI), the PSAP or another device queries an ALI database for information on the physical location of the calling party's phone. An ALI database stores records of telephone numbers with each record containing information (such as a street address) or a physical location corresponding with a telephone number. Responsive to a query from the PSAP, the ALI database returns the location information for the calling party. With the telephone number and the location information, the operator can more effectively handle the emergency call. Other countries have emergency services similar to this.
E9-1-1 service is more easily implemented for landline phones where a location of a phone is easily determined. Mobile devices, such as cell phones, PCS phones, etc., present another problem. The locations of mobile devices are not fixed by definition, which makes determining their location more of a challenge as compared to landline phones. Regulatory bodies, such as the Federal Communications Commission (FCC) in the United States, have set forth regulations that networks must be able to determine the location of mobile devices for emergency calls (e.g., 9-1-1 calls in the U.S.). Other location-based services are also being offered that need to determine the location of mobile devices. If a mobile device is GPS enabled, then the device can provide its location to the network. If the mobile device is not GPS enabled, then the network has the duty to determine the location of the mobile device.
A mobile network, such as a cellular or PCS network, can estimate the location of a mobile device based on the location of the cell presently providing service to the mobile device, such as through a cell identifier (cell ID). The mobile network may also use triangulation among multiple cells, time of arrival (TOA) information, and other data to more accurately determine the location of the mobile device.
Another type of mobile network gaining popularity is Unlicensed Mobile Access (UMA) networks. UMA networks use portions of the unlicensed spectrum for communication with protocols such as Bluetooth, 802.11b, 802.11g, etc., and are also sometimes referred to as WiFi networks. UMA networks are becoming more popular in private residences and in public “hot spots,” such as in airports, book stores, coffee shops, etc. UMA networks generally provide a higher bandwidth than cellular or PCS networks, which provides an opportunity for placing phone calls, surfing the Internet, checking email, etc.
UMA networks are being implemented as an integral part of licensed mobile networks, such as cellular or PCS networks, to allow for dual modes of communication. A typical GSM cellular network includes a Mobile Switching Center (MSC) that switch calls between a plurality of base station controllers, other MSC's, and the Public Switched Telephone Network (PSTN). Each of the base station controllers connects to a plurality of base stations that provide the radio interface to the mobile devices.
UMA networks include a plurality of UMA Network Controllers (UNC) connected to one or more access points over a broadband data network. The UNC connects to the MSC in the cellular network and acts as a gateway between the UMA network and the cellular network. The UNC converts the voice traffic from the access points to a format used by the MSC. The UNC also converts the voice traffic from the MSC to a format used in the UMA network. The UNC and the UMA network may be transparent to the MSC, and the MSC may recognize the UNC as just another base station controller in the cellular network.
Dual-mode mobile phones are capable of switching between the licensed mobile network and the UMA network for communication. UMA networks and dual-mode mobile devices are described in a provisional patent application entitled “System and Method for Routing Special Number Calls from a Dual-Mode Wireless Communications Device”, filed on Dec. 28, 2005 and having the Ser. No. 60/754,498, and a provisional patent application entitled “System and Method for Using Access Point Identification to Determine Location of a Dual-Mode Mobile Unit Operating in the Unlicensed Mode”, filed on Jan. 27, 2006 and having the Ser. No. 60/762,651, which are both incorporated by reference as if set forth herein in their entirety.
One problem with UMA networks is that present mechanisms for determining the location of a mobile device either do not exist or are not sufficient. The inability to accurately determine the location of a mobile device in a UMA network is especially a problem for special number calls (e.g., a 9-1-1 call) or location-based services that require the location of the mobile device. For emergency calls, the location of a mobile device in a UMA network is needed to route the emergency calls to the proper PSAP. The location of the mobile device is also stored in a location database that is accessible to the PSAP.